Roots of Polynomial The number c is a root of a polynomial p(x), if p(c)=0.
( U0 m" V/ x2 ^( i+ |3 Q An n-th order polynomial has n complex roots.
0 ?. s# j! |6 V. Y9 n `& ~/ o Example:% y7 W- Y8 B6 B9 q% Q$ T
2 is a root of polynomial p(x)=x-2,since p(2)=2-2=0.7 H# r8 @8 }5 `4 [
1 is a root of polynomial p(x)=x2-3x+2,since p(1)=12-3*1+2=0.
' v0 e e7 U# L$ w% p" J6 x Remember:
5 {- W c0 }# I" K. p: Q, H A polynomial may not have any real root:p(x)=x2+1 does not have any real root, since p(x)>=1 for all real x.
. X: O. ~9 U; V9 D 由于美国数学基础教育的难度增加导致数学考试越来越难,但新gre数学复习考点都是高中时候学到的知识点,考生不要过于紧张,把基本概念弄明白,再记住一些新版gre数学必备的词汇,那么相信新版gre数学应该没有问题。 |